Floor drain with drain field

ABSTRACT

A floor drain system includes a tray having a well, a riser installable in the tray, and a plurality of beads fixable within the well and outside the riser. The tray includes a perimeter flange attachable to a subfloor, and the well extends downwardly from the perimeter flange. A hollow stem extends downwardly from the well and is connectable to a drain pipe. The riser is installable at a selectable elevation within the stem of the tray, and has an interior drainage pathway orientable toward the drain pipe. The riser defines a seepage pathway outside of the riser and within the stem. The plurality of beads, when fixed together, form a permeable drain field bonded to both the riser and the tray, whereby liquid can pass through the drain field to the seepage pathway.

BACKGROUND

1. Field of the Invention

The present disclosure relates generally to floor drains, such as for tiled showers and the like. More particularly, the present disclosure relates to a floor drain having a permeable drain field below a finished floor structure and surrounding the drain body.

2. Related Art

Floor and drain structures for tiled showers and the like frequently incorporate a waterproofing layer in the form of a “shower pan” below a tiled surface and mortar bed. Beneath the pan layer, another thin mortar bed called a pre-slope is frequently attached directly onto the sub-floor, creating a slope extending upward from the drain flange (i.e. the top flange of the drain pipe) to the perimeter walls of the shower enclosure. A substantially thick structural bed of mortar is then installed over the top of the pan, as a base for the tile, stone, or other finished flooring material.

There are some limitations and drawbacks to the use of shower pans. The pan is generally not bonded or fastened either to the substrate beneath or to the mortar bed above. This type of configuration, called a “floating mortar bed”, can present a drainage concern. Each time the shower is used, a new supply of water and organic material (skin, soap, conditioners etc.) is introduced to the mortar bed through perimeter cracks and grout lines between tiles. Shower floor structures of this construction tend to retain significant water in the mortar bed, which drains out slowly. With daily use, the floor structure is repeatedly saturated with water and could take weeks of non-use to dry out completely. This combination of conditions creates an environment ripe for mold growth.

Recently, “surface bonded” waterproofing products for tiled shower structures have been introduced to the market. The common characteristic among these products is that they bond adequately to the mortar bed below and tile bonds adequately to their top surface with commonly available thinset mortar. Their proper use eliminates the need for a shower pan and floating mortar bed and greatly simplifies shower floor construction. The introduction of such products has created the demand for a new generation of drains to which these can be attached, at the top mortar bed surface, with a secure and water-tight connection. Nevertheless, with such drains it is also desirable to provide a means for water held within the tile, mortar and grout to escape to the drain.

The elimination of the “floating mortar bed” type construction greatly reduces the amount of trapped water beneath the tiled surface. Nevertheless, there is still a potential for water to seep under the tile or other floor surface before reaching the drain. Unless this seepage is allowed a drainage pathway, it can collect beneath the surface around the drain, creating a breeding ground for mold, etc.

SUMMARY

It has been recognized that it would be advantageous to develop a floor drain system that provides a secure watertight means for top surface attachment of “Surface Bonded” waterproofing membrane materials and an escape pathway for under-tile seepage.

In accordance with one embodiment thereof, the present invention provides a floor drain system including a tray having a well, a riser installable in the tray, and a plurality of beads fixable within the well and outside the riser. The tray includes a perimeter flange attachable to a subfloor, and the well extends downwardly from the perimeter flange. A hollow stem extends downwardly from the well and is connectable to a drain pipe. The riser is installable at a selectable elevation within the stem of the tray, and has an interior drainage pathway orientable toward the drain pipe. The riser defines a seepage pathway outside of the riser and within the stem. The plurality of beads, when fixed together, form a permeable drain field bonded to both the riser and the tray, whereby liquid can pass through the drain field to the seepage pathway.

In accordance with another aspect thereof, the invention provides a drain tray for a floor drain. The drain tray includes a perimeter flange configured to attach to a subfloor, a well, extending downwardly within the perimeter flange, and a stem, downwardly extending from the well. The stem is configured to communicate with a drain conduit, and to receive a drain body attached thereinto. The stem defines a seepage pathway, outside of the drain body, from the well to the drain conduit. The well is configured to receive a plurality of beads, fixable via a chemical solvent to form a permeable drain field bonded to both the drain body and the well, whereby liquid entering the drain field outside of the drain body can enter the seepage pathway.

In accordance with yet another aspect thereof, the invention provides a floor drain system, including a drain tray, having a well and a stem, a drain body, installable at a selectable elevation within the drain tray, a quantity of polymer beads, sufficient to substantially fill the well, and a chemical solvent. The drain tray has a perimeter flange configured to attach to a subfloor. The well is disposed within and extends downwardly from the perimeter flange, and the stem extends downwardly from the well and is configured to communicate with a drain pipe. The drain body has an interior drainage pathway, and defines a seepage pathway between the drain body and the stem. The chemical solvent is suitable to be poured over the polymer beads within the well, and to bond the beads to each other and to the drain tray and the drain body, forming a permeable drain field whereby liquid in the well and outside the drain body can pass to the seepage pathway.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional features and advantages of the invention will be apparent from the detailed description which follows, taken in conjunction with the accompanying drawings, which together illustrate, by way of example, features of the invention, and wherein:

FIG. 1 is a perspective view of one embodiment of a floor drain body with a drain grate in place;

FIG. 2 is a perspective view of the drain grate of FIG. 1 with the grate removed;

FIG. 3 is a top perspective view of a drain tray configured to receive a drain body, such as that shown in FIGS. 1 and 2;

FIG. 4 is a top perspective view of the drain tray of FIG. 3 with a drain body like that of FIGS. 1 and 2 installed therein;

FIG. 5 is a side, cross-sectional view of the drain tray of FIG. 3 connected to a drain pipe;

FIG. 6 is a side, split cross-sectional view of the drain tray and drain body of FIG. 5, with the drain tray shown installed in two different types of subfloor, with a bead drain field installed around the drain body and a waterproofing membrane and finished floor installed over the drain tray and drain field on one side;

FIG. 7 is a perspective view of a random group of beads bonded together;

FIG. 8 is a perspective view of a bead having a tapered hole; and

FIG. 9 is a cross-sectional view of the bead of FIG. 9.

DETAILED DESCRIPTION

Reference will now be made to exemplary embodiments illustrated in the drawings, and specific language will be used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Alterations and further modifications of the inventive features illustrated herein, and additional applications of the principles of the inventions as illustrated herein, which would occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the invention.

As noted above, floor structures for tiled showers and the like have frequently incorporated a waterproofing layer in the form of a “shower pan” below the tiled surface and mortar bed beneath. Still lower, beneath the pan layer, a thin mortar bed called a pre-slope is attached directly onto the sub-floor, creating a slope from the drain flange (i.e. the top flange of the drain pipe) rising to the perimeter walls of the shower enclosure. Installed over top of the pre-slope, shower pans were originally constructed using sheet metal materials. Copper and lead were the choices because they would not rust, could be worked to shape and soldered to cast iron drain flanges. Such flanges were generally placed at or slightly above the subfloor elevation and provided a surface for a secure water-tight connection. Later, rubber and then flexible plastic materials became more economical and began to replace metal shower pans. These new pan materials gave rise to a new generation of drain fittings incorporating clamping collars installed in combination with a sealant material to create a secure water tight seal to the flange.

There are some limitations to the use of shower pans. Their use has generally been limited to waterproofing shower floors and thresholds only. A pan will typically extend up perimeter walls only about six inches. At corners these materials become more difficult to work with, and are frequently folded rather than cut to maintain water-tight integrity. Folding these materials at transitions can create localized areas where there are multiple layers of material three to six layers thick. Extending these materials up walls and using them to cover features such as built-in shower benches and wall niches can become problematic and impractical.

The complexity of shower structures using the shower pan construction method is increased by the fact that the pan is frequently not bonded or fastened either to the substrate beneath or to the mortar bed above. This type of configuration is called a “floating mortar bed.” This structural bed of mortar built over the top of such pans has to be sufficiently strong to withstand movement from foot traffic, to support bridging created by settling, and other natural forces. In the United States, the National Tile Council and other code agencies specify that such a floating mortar bed structure is to be a minimum 1.25″ thickness at the drain. The purpose for this floating structure is to create a suitable surface onto which ceramic tile and stone materials can be bonded.

The floating mortar bed and shower pan structure as described above has been a controversial subject within the tile industry in recent years. At the present time it is still the most commonly used method. This is likely due to the economy of the materials used and that this method is the traditional method being taught. Many traditional tile setters believe it is still the best and most proven method. Others believe it has always been problematic. The most common issue inherent with this structure is that the floating mortar bed is, by design, frequently saturated with water. Each time the shower is used, a new supply of water and organic material (skin, soap, conditioners etc.) is introduced to the mortar bed through cracks and grout lines between tiles. This combination of conditions creates an environment ripe for mold growth. Many in the industry agree that a properly conceived shower floor structure ought to become completely dry within a few hours after use each day to remain mold free. This does not happen with this kind of shower floor construction.

Within the past few years several companies have begun to develop “surface bonded” water proofing products and systems for tiled shower structures that eliminate the need for a shower pan and floating mortar bed. Some of these new systems are substantially thinner and require less material than prior methods. Some are also better at allowing seepage water to evaporate. In spite of these improvements, however, there is still a significant potential for water to seep under the tile or other floor surface before reaching the drain. Despite the use of waterproofing membranes and the like, over time there is always some likelihood that water will seep through cracks in the finished floor, and migrate downward. Unless this seepage also has a drainage pathway, it can provide a breeding ground for mold, etc., and can shorten the life of the floor structure.

The present disclosure provides a drain mechanism and system whereby surface-applied waterproofing materials can create a water-tight seal and secure attachment at the top mortar bed surface without the need for a clamping collar and mechanical fasteners. It also provides a system whereby water that might otherwise remain trapped within grout lines and mortar can migrate under the pull of gravity and escape to the drain opening.

The figures herein show an embodiment of a floor drain system that provides an alternate drainage pathway for seepage. Shown in FIG. 1 is a drain body or riser 10 with a grate 12 having drain openings 13. The drain body is shown with the grate removed in FIG. 2. This drain body 10 is a one-piece unit, having a generally rectangular upper portion 14 defining an inlet, and a circular lower portion 16 defining an outlet and being configured to mate with an underdrain structure (e.g. like that shown in FIG. 3). It is to be understood that, while the drain body shown in FIGS. 1 and 2 has a rectangular inlet, drain bodies having inlets of other shapes, such as circular, can also be used. The lower portion of the drain body includes external helical threads 18 for connection to the underdrain, allowing the height of the drain inlet to be adjusted by rotating the drain body. The drain body can be of an injection-molded polymer, such as ABS (Acrylonitrile Butadiene Styrene) plastic, allowing it to be strong and lightweight.

The inlet portion 14 of the drain body 10 includes a shoulder 20 on its inner perimeter, for supporting the drain grate 12. Surrounding the shoulder is a grout rim 22 that is integral with the drain body. The grate 12 is supported only around it's perimeter by a narrow shelf (i.e. shoulder 20) in the drain body 10. Just inside and below that shelf is a near-vertical surface 21 that extends down to the floor of the bowl 30. Against this surface an inner perimeter rib or wall of the grate frame can make a light friction fit. The inner surface of the grout rim includes 90 degree filleted corners 26. This configuration helps reduce binding of the grate and allows for a wide selection of grate opening configurations. The drain body can also include a step or recess 28 in the bowl floor 30, which can allow for the inclusion of a hair trap device (not shown).

By design, the bowl 30 of the drain body 10 is relatively deep (compared to the size of the grate openings 13). This helps create a shadow and a blacked-out effect that is very desirable, especially where the drain body is black or some other dark color. When viewed from the top through the openings 13 in the grate 12, the visibility of any build-up of soap scum, scale and hair will be substantially reduced. The grate looks clean and beautiful and is not detracted by a view of scum build up just below the surface.

The grout rim 22 provides a sharp termination at the top edge of the drain body 10, and becomes substantially hidden to the eye when embedded into an adjacent grout line. When a drain grate 12 is inserted into the inlet portion 14 and supported by the shoulder 20, friction between the vertical surface 21 and a perimeter rib (not shown) of the drain grate's frame holds the grate in place. A small clearance can be maintained between the grate 12 and the grout rim 22 to allow for drainage immediately around the slightly elevated grate.

Around the outer sides 34 of the inlet portion 14 of this embodiment of the drain body 10 are undercut grout locking features that help anchor the drain body with surrounding mortar and grout material. The undercut grout locking features can include a horizontal undercut edge 42, and tapered or dovetail surfaces associated with vertical buttresses 36, to cause the buttresses to interlock with surrounding grout, allowing the grout to capture the drain body and hold it in position in a dovetail arrangement. The buttresses have a dovetail shape that becomes wider as the buttress extends away from the sidewall 34 of the drain body. This provides dovetail surfaces that are angled toward the drain body, so that a mechanical interlock is created with grout material that surrounds the drain body. Since the dovetail surfaces of the buttresses are angled with respect to a vertical plane, and the angled undercut surface of the undercut edge 42 is angled with respect to a horizontal plane, the undercut edge and the dovetail buttresses combine to anchor the drain body with respect to both vertical and horizontal movement.

The outer sides 34 of the drain body can also include vertical darts 48 below or along the horizontal undercut 42 to improve plastic flow to thin wall sections during the molding process, as well as to add rigidity. Given their angular faces, the darts also help provide additional anchorage of the drain body in the surrounding grout material, while their small size in relation to the buttresses does not weaken the anchoring grout material between the buttresses.

Since it is installed using only a light friction fit and no screws or other fasteners, the drain grate 12 can be easily removed, such as by using a T-handle grate removal tool (not shown), or other suitable tool. During installation of the drain body and construction of the surrounding floor structure, a solid flat plug can be installed in the drain body in place of the grate to prevent construction debris from falling into the drain, prevent damage to the grate, and to stabilize the knife edge rim 22 of the drain body and help maintain the shape of the inlet.

As noted above, the helical threads 18 on the lower stem 16 of the drain body can be screwed into a threaded receiving end of a drain pipe. However, these threads can also attach to other structure, such as a bonding flange or drain tray 200, shown in FIGS. 3-6. The drain tray is shown in cross-sectional view in FIGS. 5 and 6. Referring to FIG. 3, the tray 200 generally includes a perimeter flange 202, a depressed well section 204 inside the perimeter flange, and a tubular lower stem 206 that is configured to attach to a drain pipe 208.

The perimeter flange 202 is configured to attach to or be embedded within a subfloor, with a finished floor installed over the top of it. Such an installation is shown in FIG. 6. As used herein, the phrase “attachable to a subfloor” is intended to include any type of installation upon or within or in association with a subfloor of any type. Thus, whether the tray 200 is attached atop a wood subfloor 308, embedded in a concrete subfloor 310, or attached in any other way, with a finished floor 302 installed above it. The top surface of the perimeter flange can include ribs or ridges 216 that help provide a strong mechanical connection to water-proofing, mortar or other floor materials that are installed over it. For example, as shown in FIG. 6, an emulsion waterproofing membrane 300 is installed over the perimeter flange.

As shown in FIGS. 3, 5 and 6, the lower stem 206 of the drain tray 200 can be configured to attach to a collar or adapter 220 that in turn attaches to a drain pipe 208. This can be an adhesive or solvent weld-type of connection. Alternatively, the lower stem 206 can attach directly to a drain pipe, such as by having external helical threads (not shown) that can be threadedly attached to a drain pipe, in a manner similar to the way in which the drain body 10 is attached to the tray 200. Any other suitable method for attaching the tray to the drain pipe 208 can also be used.

The interior 222 of the stem 206 includes an internal helical thread 224, having drainage gaps 226. These structures are most easily viewed in FIG. 5. In the embodiment that is shown, the helical thread 224 defines a single revolution. Alternatively, multiple helical threads can also be used. This single helical thread is configured to mesh with the external helical threads 18 of the stem of the drain body 10. The gaps 226 in the helical thread 224 make this thread discontinuous and allow drainage of moisture from the well 204 of the drain tray 200, as discussed below. Where multiple threads are used to connect to the drain body 10, gaps can be provided in each thread to provide the drainage pathway.

Below the helical thread 224 are several vertical friction bars 228. As shown in FIGS. 5 and 6, the outer helical threads 18 of the stem 16 of the drain body 10 intermesh with the single thread 224 of the drain tray, and self-thread by digging into the friction bars 228. This self-threading feature provides resistance to rotation of the drain body during installation, and also provides greater stability to the drain body than would otherwise result from connection with the single helical thread alone. The drain body 10 can be rotated while threading onto the single thread 224 and the friction bars 228, until reaching a desired elevation, so that the grate 12 of the drain body will match the elevation of the finished floor.

With reference to FIG. 5, the depressed well section 204 is defined by a perimeter wall 230 and a floor 232, which leads to the interior 222 of the stem 206. The floor 232 of the well can be sloped toward the interior 222 of the stem to facilitate drainage. It is to be recognized, however, that the well section can be configured in a variety of shapes other than that shown. For example, the junction between the wall 230 of the well 204 and the floor 232 can be curved much more than shown in FIG. 5. Indeed, rather than having a substantially vertical wall and horizontal floor, the entirety of the well 204 can be defined by a single surface that continuously curves from its intersection with the horizontal perimeter flange 202, to its junction with the vertical stem 206 of the tray. Other shapes can also be used, so long as there is adequate room for installation of the drain body, and the insertion of beads to create a drain field, as discussed below. Additionally, the well can be square or rectangular, or some other shape, in addition to the circular shape shown in the figures.

Referring to FIG. 6, after the drain body 10 is installed in the stem 206 of the drain tray 200 and placed at the desired height, the well 204 can be filled with polymer beads 250 up to the level of the perimeter flange 202. The well 204 is larger across than the maximum dimension of the upper portion 14 of the drain body 10. Thus, whether the drain body is square, as shown in the figures, or any other shape, there will be openings around the sides of the drain body into which the beads 250 can be poured. Beads 250 filling one side of the well 204 are shown in FIG. 6. Once the well is filled, a chemical solvent is then poured over the beads, and partially welds (via solvent welding) the beads together, while still leaving void spaces between them. Views of the finished bead installation are shown in FIGS. 6 and 7.

The mass of beads 250 solvent welded together within the well 204 creates a bead drain field 252, providing a permeable matrix with significant void spaces. The matrix of void spaces provides a drainage pathway for seepage to reach the interior 222 of the stem 206 of the drain tray 200, and thence drain into the drain pipe 208, thus allowing more rapid and complete drainage of the subfloor system above the drain. Additionally, the drain body 10, drain tray 200 and the beads 250 can be of common or similar polymer materials. For example, in one embodiment the drain body, tray and beads are of ABS plastic. Consequently, the solvent that causes the beads to bond together will also bond the mass of beads to both the drain body and the tray. A solvent that is suitable for ABS plastic in this embodiment is lacquer thinner. The bonding action of the solvent fixes the position of the drain body 10 with respect to the tray 200 and the bead drain field, and creates a solid construction.

To complete the installation, an emulsion water-proofing membrane 300 can be installed over the top of a portion of the bead drain field 252 and the perimeter flange 202. Other types of waterproofing structures can also be used. A finished floor surface 302, such as tile 304 installed on a bed of mortar 306, shown in FIG. 6, can then be placed atop the water-proofing membrane 300 and installed flush with the top of the drain grate 12 and against the side wall 34 of the drain body 10. The mortar bed extends up to the side wall 34 of the drain body 10 over the bead drain field 252. However, the waterproofing membrane 300 only extends partway across the top of the bead drain field. This allows moisture that is within the mortar to drain down into the bead drain field 252, and reach the seepage pathway that leads to the drain, thus allowing the mortar bed 306 to drain and dry more quickly and completely.

The bonded bead drain field 252 serves as a 3D bonding matrix for the waterproofing emulsion 300 or a bonded sheet membrane (not shown) that is installed above it. Emulsion-based waterproofing materials bond to surrounding materials, but the bond can be relatively weak to ABS and PVC plastic materials. Once cured, an emulsion-based waterproofing membrane can be peeled as a sheet from many types of materials. Advantageously, a waterproofing emulsion can be worked into and penetrate around the bonded beads 250 and the void spaces in the top few layers of the drain field matrix 252, creating a three dimensional bond with the top portion of the bead matrix. Since the bead drain field is bonded as a unit to the drain body and the drain tray, this creates a mechanical connection between the waterproofing material and the drain installation, and helps eliminate the need for a mechanical clamping plate and fasteners to attach a waterproofing membrane, as are commonly used in drain installations. The section of the bead matrix 252 to which the waterproofing material bonds can be about two beads deep to form an adequate bond.

The bead drain field 252 surrounding the drain body 10 provides several benefits. First, the mass of beads 250 solvent welded together holds the drain body 10 in the desired place, and adds strength to the complete drain installation. It also provides a permeable drain field 252 that directs any seepage down and around the outside of the stem 16 of the drain body, and into the drain pipe 208.

In one embodiment, the beads 250 are of ABS plastic, about 5 mm diameter, and are generally spherical. The beads can be regular and round or somewhat irregular. Different sizes and shapes can be used. A mass 400 of bonded beads 250 is shown in FIG. 7. These beads are generally spherical and of a common size. The beads can be solid or, as shown in FIGS. 7-9, the beads can have holes in them. In these figures, the beads each have a tapered hole 402 extending through their center. FIG. 9 shows a cross-sectional view of a single bead 250 with a tapered hole 402 extending through it. The tapered holes can provide a pathway for drainage and/or a pathway for the solvent. This facilitates bonding of the mass of beads during installation, and holes that do not fill with dissolved plastic material will provide additional drainage pathways for water. The holes also make the beads lighter and provide more surface bonding area, while providing an open matrix that has sufficient structural strength to support weight above it.

The drain system with the bead matrix drain field 252 disclosed herein has several desirable characteristics. First, the bead drain field 252 promotes weep drainage below the finished floor surface 302. This helps make drainage faster and more complete, thus inhibiting the growth of mold and the like, and contributing to the integrity and long life of the finished floor installation. Polymer beads are also very useful for a drain field because they are less likely to support mold growth than organic fibers or mineral aggregate. Additionally, plastic beads of this size tend to shed water rather than absorbing it, and do not support capillary action.

The use of loose beads to create a drain field also increases the flexibility and ease of use of this system. The loose beads 250 take the shape of the well 204 or whatever cavity exists around the drain body, and, prior to fixing them with the solvent, can be easily moved or adjusted like a fluid, allowing a user to easily adjust the final position of the drain body 10. Since the beads and drain body are easily repositionable prior to introduction of the solvent, there is no inconvenience of a chemical reaction (e.g. of an adhesive) dictating a cure time before which all adjustments must be final. The beads 250 and the drain body 10 and drain tray 200 remain clean and dry while positioning the drain body in the desired place. Custom shapes are not needed for the well or for the beads. The manufactured bead size can be very consistent, so that the beads are all the same size and shape. This allows control of and helps maximize the quantity of void space between the beads. The use of initially loose beads placed around the drain body also allows for multiple choices of the size and shape of the drain inlet and cover options.

The solvent weld approach also avoids some of the undesirable effects of chemical adhesives. First, creating the bead drain field 252 does not require mixing of adhesive and beads, which makes it simple to install. This system is also economical because a one part solvent can be used to bond the beads 250 together, as opposed to a two part adhesive. Additionally, an adhesive binder will create an adhesive film having some thickness, which can clog drainage and bonding passageways. Instead, by use of a solvent weld approach, adjacent polymer drain components (i.e. the beads and drain body and tray) are fused together of the material of the beads themselves, and no additional quantity of material is introduced which could clog the drain field.

The bead drain field 252 also increases the strength of the overall drain structure. The solvent weld provides a quick set. Once doused with solvent, the bead matrix and drain components are very rapidly fused in position, allowing work in surrounding areas to begin as soon as the solvent is able to flash off. Typically this happens within 10 minutes, but can be much quicker if air flow is increased via a fan, compressed air etc. With all components solvent bonded together, an enhanced structure is created that is stronger than the individual components alone.

It is to be understood that the above-referenced arrangements are illustrative of the application of the principles of the present disclosure. It will be apparent to those of ordinary skill in the art that numerous modifications can be made without departing from the principles and concepts of the invention as set forth in the claims. 

1. A floor drain system, comprising: a tray, having a perimeter flange attachable to a subfloor, a well extending downwardly from the perimeter flange, and a hollow stem extending downwardly from the well and connectable to a drain pipe; a riser, installable at a selectable elevation within the stem, having an interior drainage pathway orientable toward the drain pipe, and defining a seepage pathway that permits fluid communication between a region outside of the riser and an interior of the stem; and a plurality of beads, fixable within the well outside of the riser, to form a permeable drain field bonded to both the riser and the tray, whereby liquid can pass through the drain field to the seepage pathway.
 2. A floor drain system in accordance with claim 1, the riser further comprising a top inlet portion configured to receive a drain grate in only a friction fit.
 3. A floor drain system in accordance with claim 1, wherein the beads are fixable via a chemical solvent, selected to produce a solvent weld between and among the beads and the riser and the tray.
 4. A floor drain system in accordance with claim 1, wherein the tray, the riser and the beads are comprised of ABS plastic.
 5. A floor drain system in accordance with claim 1, wherein the beads are about 5 mm in size and substantially regular in shape.
 6. A floor drain system in accordance with claim 1, further comprising a hole extending through each bead.
 7. A floor drain system in accordance with claim 1, the tray further comprising: a discontinuous helical thread, disposed within the interior of the stem; and the riser further comprising a downwardly oriented stem, having a plurality of external helical threads configured to mate with the discontinuous helical thread of the stem of the tray, whereby the riser threads into the tray, the discontinuities of the helical thread of the stem defining the seepage pathway.
 8. A floor drain system in accordance with claim 7, further comprising at least one vertical friction bar, positioned within the stem of the tray and below the helical thread, configured to self-thread with the external helical threads of the stem of the riser.
 9. A floor drain system in accordance with claim 1, the perimeter flange of the tray further comprising ridges, configured for bonding with a waterproofing layer placed thereabove.
 10. A floor drain system in accordance with claim 1, wherein the tray is substantially circular in shape, and the riser has a top inlet portion that is substantially rectangular.
 11. A drain tray for a floor drain, comprising: a perimeter flange configured to attach to a subfloor; a well, defined by a wall extending downwardly from the perimeter flange; a stem, downwardly extending from the well, configured to communicate with a drain conduit, and to receive a drain body attached thereinto, the stem defining a seepage pathway that permits drainage from outside of the drain body, into the well and into the drain conduit; the well being configured to receive a plurality of beads, fixable via a chemical solvent to form a permeable drain field bonded to both the drain body and the wall of the well, whereby liquid entering the drain field outside of the drain body can enter the seepage pathway.
 12. A drain tray in accordance with claim 11, wherein the stem includes an internal helical thread configured to mate with external helical threads of the drain body, the helical thread defining a plurality of gaps defining the seepage pathway.
 13. A drain tray in accordance with claim 12, further comprising a plurality of self-threading protrusions within the stem of the tray and below the helical thread configured to self-thread with the helical threads of the drain body.
 14. A drain tray in accordance with claim 11, further comprising a plurality of ridges, disposed atop the perimeter flange, configured to bond with a waterproofing layer placed thereabove.
 15. A drain tray in accordance with claim 11, wherein the tray is substantially circular in shape.
 16. A floor drain system, comprising: a drain tray, having a perimeter flange configured to attach to a subfloor, a well disposed within and extending downwardly from the perimeter flange, and a stem extending downwardly from the well and configured to communicate with a drain pipe; a drain body, installable at a selectable elevation within the stem of the drain tray, having an interior drainage pathway, and defining a seepage pathway between the drain body and the stem; a quantity of polymer beads, sufficient to fill the well substantially up to the perimeter flange; and a chemical solvent, suitable to be poured over the polymer beads within the well and to bond the beads to each other and to the drain tray and the drain body, forming a permeable drain field whereby liquid in the well and outside the drain body can pass to the seepage pathway.
 17. A floor drain system in accordance with claim 16, wherein the stem of the drain tray includes an internal helical thread configured to mate with external helical threads of the drain body, the helical thread including a plurality of gaps defining the seepage pathway.
 18. A floor drain system in accordance with claim 17, further comprising a plurality of self-threading protrusions, within the stem of the drain tray and below the helical thread, configured to self-thread with the helical threads of the drain body.
 19. A floor drain system in accordance with claim 16, wherein the drain tray, the drain body, and the beads comprise ABS plastic, and the solvent comprises lacquer thinner.
 20. A floor drain system in accordance with claim 16, further comprising a plurality of ridges, disposed atop the perimeter flange, configured to bond with a waterproofing layer placed thereabove. 